1. Field of the Invention
The present invention relates to a laminated LC filter preferably for use in an electronic device or other suitable device, for example.
2. Description of the Related Art
An existing laminated LC filter is composed of a laminate in which a dielectric layer and an electrode layer are laminated; and a plurality of LC resonators provided in the laminate.
For example, an LC filter 100 disclosed in Japanese Unexamined Patent Application Publication No. 10-190391 as shown in FIG. 9 is known. Specifically, the LC filter 100 includes inductor portions 92 and 93 in which coils 86 and 87 are included, respectively. Each of the coils 86 and 87 is formed by laminating sheets in which coil conductors and via electrodes for defining a relay are provided, and their axial directions are perpendicular to input/output external electrodes 95 and 96. In addition, a ground electrode 90 and an electrode 91 are disposed in a capacitor portion 94 so as to face each other.
An end of the coil 86 is electrically connected to an end 91a of the electrode 91 via a connection electrode 99 provided on a side surface of the filter 100 on the near side. An end of the coil 87 is electrically connected to the other end 91b of the electrode 91 via a connection electrode 80 provided on a side surface of the filter 100 on the far side.
However, in the LC filter disclosed in Japanese Unexamined Patent Application Publication No. 10-190391, the directions of magnetic fields of the coils 86 and 87 are parallel to a board on which the LC filter is mounted. Thus, radiation of magnetic flux influences an adjacent electronic component. In addition, the coil conductors are mainly formed of pattern printing electrodes, and hence an inductance with a great Q value is not obtained. Thus, the insertion loss of the filter increases.